Commit 87d68730 authored by Dong Aisheng's avatar Dong Aisheng Committed by Samuel Ortiz

mfd: Add syscon driver based on regmap

Add regmap based syscon driver.
This is usually used for access misc bits in registers which does not belong
to a specific module, for example, IMX IOMUXC GPR and ANATOP.
With this driver, client can use generic regmap API to access registers
which are registered into syscon.
Reviewed-by: default avatarMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: default avatarStephen Warren <swarren@wwwdotorg.org>
Signed-off-by: default avatarDong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: default avatarSamuel Ortiz <sameo@linux.intel.com>
parent a435ae1d
* System Controller Registers R/W driver
System controller node represents a register region containing a set
of miscellaneous registers. The registers are not cohesive enough to
represent as any specific type of device. The typical use-case is for
some other node's driver, or platform-specific code, to acquire a
reference to the syscon node (e.g. by phandle, node path, or search
using a specific compatible value), interrogate the node (or associated
OS driver) to determine the location of the registers, and access the
registers directly.
Required properties:
- compatible: Should contain "syscon".
- reg: the register region can be accessed from syscon
Examples:
gpr: iomuxc-gpr@020e0000 {
compatible = "fsl,imx6q-iomuxc-gpr", "syscon";
reg = <0x020e0000 0x38>;
};
......@@ -1004,6 +1004,14 @@ config MFD_ANATOP
MFD controller. This controller embeds regulator and
thermal devices for Freescale i.MX platforms.
config MFD_SYSCON
bool "System Controller Register R/W Based on Regmap"
depends on OF
select REGMAP_MMIO
help
Select this option to enable accessing system control registers
via regmap.
config MFD_PALMAS
bool "Support for the TI Palmas series chips"
select MFD_CORE
......
......@@ -132,4 +132,5 @@ obj-$(CONFIG_MFD_PALMAS) += palmas.o
obj-$(CONFIG_MFD_RC5T583) += rc5t583.o rc5t583-irq.o
obj-$(CONFIG_MFD_SEC_CORE) += sec-core.o sec-irq.o
obj-$(CONFIG_MFD_ANATOP) += anatop-mfd.o
obj-$(CONFIG_MFD_SYSCON) += syscon.o
obj-$(CONFIG_MFD_LM3533) += lm3533-core.o lm3533-ctrlbank.o
/*
* System Control Driver
*
* Copyright (C) 2012 Freescale Semiconductor, Inc.
* Copyright (C) 2012 Linaro Ltd.
*
* Author: Dong Aisheng <dong.aisheng@linaro.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/err.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
static struct platform_driver syscon_driver;
struct syscon {
struct device *dev;
void __iomem *base;
struct regmap *regmap;
};
static int syscon_match(struct device *dev, void *data)
{
struct syscon *syscon = dev_get_drvdata(dev);
struct device_node *dn = data;
return (syscon->dev->of_node == dn) ? 1 : 0;
}
struct regmap *syscon_node_to_regmap(struct device_node *np)
{
struct syscon *syscon;
struct device *dev;
dev = driver_find_device(&syscon_driver.driver, NULL, np,
syscon_match);
if (!dev)
return ERR_PTR(-EPROBE_DEFER);
syscon = dev_get_drvdata(dev);
return syscon->regmap;
}
EXPORT_SYMBOL_GPL(syscon_node_to_regmap);
struct regmap *syscon_regmap_lookup_by_compatible(const char *s)
{
struct device_node *syscon_np;
struct regmap *regmap;
syscon_np = of_find_compatible_node(NULL, NULL, s);
if (!syscon_np)
return ERR_PTR(-ENODEV);
regmap = syscon_node_to_regmap(syscon_np);
of_node_put(syscon_np);
return regmap;
}
EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_compatible);
struct regmap *syscon_regmap_lookup_by_phandle(struct device_node *np,
const char *property)
{
struct device_node *syscon_np;
struct regmap *regmap;
syscon_np = of_parse_phandle(np, property, 0);
if (!syscon_np)
return ERR_PTR(-ENODEV);
regmap = syscon_node_to_regmap(syscon_np);
of_node_put(syscon_np);
return regmap;
}
EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_phandle);
static const struct of_device_id of_syscon_match[] = {
{ .compatible = "syscon", },
{ },
};
static struct regmap_config syscon_regmap_config = {
.reg_bits = 32,
.val_bits = 32,
.reg_stride = 4,
};
static int __devinit syscon_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct syscon *syscon;
struct resource res;
int ret;
if (!np)
return -ENOENT;
syscon = devm_kzalloc(dev, sizeof(struct syscon),
GFP_KERNEL);
if (!syscon)
return -ENOMEM;
syscon->base = of_iomap(np, 0);
if (!syscon->base)
return -EADDRNOTAVAIL;
ret = of_address_to_resource(np, 0, &res);
if (ret)
return ret;
syscon_regmap_config.max_register = res.end - res.start - 3;
syscon->regmap = devm_regmap_init_mmio(dev, syscon->base,
&syscon_regmap_config);
if (IS_ERR(syscon->regmap)) {
dev_err(dev, "regmap init failed\n");
return PTR_ERR(syscon->regmap);
}
syscon->dev = dev;
platform_set_drvdata(pdev, syscon);
dev_info(dev, "syscon regmap start 0x%x end 0x%x registered\n",
res.start, res.end);
return 0;
}
static int __devexit syscon_remove(struct platform_device *pdev)
{
struct syscon *syscon;
syscon = platform_get_drvdata(pdev);
iounmap(syscon->base);
platform_set_drvdata(pdev, NULL);
return 0;
}
static struct platform_driver syscon_driver = {
.driver = {
.name = "syscon",
.owner = THIS_MODULE,
.of_match_table = of_syscon_match,
},
.probe = syscon_probe,
.remove = __devexit_p(syscon_remove),
};
static int __init syscon_init(void)
{
return platform_driver_register(&syscon_driver);
}
postcore_initcall(syscon_init);
static void __exit syscon_exit(void)
{
platform_driver_unregister(&syscon_driver);
}
module_exit(syscon_exit);
MODULE_AUTHOR("Dong Aisheng <dong.aisheng@linaro.org>");
MODULE_DESCRIPTION("System Control driver");
MODULE_LICENSE("GPL v2");
/*
* System Control Driver
*
* Copyright (C) 2012 Freescale Semiconductor, Inc.
* Copyright (C) 2012 Linaro Ltd.
*
* Author: Dong Aisheng <dong.aisheng@linaro.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#ifndef __LINUX_MFD_SYSCON_H__
#define __LINUX_MFD_SYSCON_H__
extern struct regmap *syscon_node_to_regmap(struct device_node *np);
extern struct regmap *syscon_regmap_lookup_by_compatible(const char *s);
extern struct regmap *syscon_regmap_lookup_by_phandle(
struct device_node *np,
const char *property);
#endif /* __LINUX_MFD_SYSCON_H__ */
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment